This invention relates to modular continuous slab casters and the like and, particularly, to a continuous caster made up of readily interchangeable caster segments, all assembled on a flat foundation mat.
Continuous casters and, particularly, continuous slab casters, have been used for several decades to convert molten steel to a continuous slab of solid metal without the intermediate steps of forming ingots, reheating ingots and rolling the ingots to slabs. There have been a multitude of designs for such continuous casters and for the many parts out of which they are assembled. They have, however, remained as immense projects requiring months and years of construction and assembly at the location of the plant and millions of dollars in costs. In the past, such continuous casters have involved vast excavations with endless forming work and concrete casting in order to produce the necessary mammoth foundations riddled with tunnels, rooms, pipe and conduit. In such prior art casters, miles of conduit wire and pipe must be individually fit and assembled in situ. Much of the machinery and structural steel for assembling the caster arrives at the site as thousands of pieces somewhat like a giant "erector set" and, like an erector set, must be painstakingly fitted together on site, frequently under less than ideal conditions. The field forces required to assemble this complicated detailed caster assembly are a major cost item, as well as a major disruptive element in a working steel plant. As a result, continuous slab casters and the like require long construction periods and massive financing efforts and are effectively beyond the means of small producers, both timewise and costwise.
I have invented a continuous casting plant assembly which drastically reduces the time and cost of field assembly. My continuous caster assembly is placed on a single flat slab, eliminating the massive tunneled and roomed underfloor support structure of the prior art. The continuous caster of this invention is made up of multiple modules, each shop assembled and tested, which are moved into place of the flat slab and in effect "plugged in" to adjacent assembled units without any need for complex infield wiring and piping. This reduces the pre-operational testing of the facility to about 15% of that normally required in prior art caster assemblies and permits a shortened, simplified field schedule of about 3 months duration involving the placement of a flat slab of concrete and the placement and connection of the pre-assembled modules. This is compared to the year or more involved in prior art caster assembly.
The caster of the present invention also has the advantage of fitting into most teeming aisles of existing steel plants and thus makes possible the use of existing buildings and cranes. In prior art casters, this was not generally possible, thus requiring new buildings and new cranes, increasing the cost and time delay.
In the present invention, all caster assemblies are independent modules that are complete with utility piping and wiring. All modules have been assembled and aligned with all associated modules prior to leaving the manufacturer. The straightening section module with integral flume channel has a number of driven rolls to transport the slab, and the short top or bottom feeding starter bar. All driven rolls are equipped with a pair of cylinders, which permit these rolls to close onto the bottom driven rolls to pinch and transport the 1/2 inch thick starter bar. Additional segment modules contain the slab through the solidification point.
The starter bar handling and charging device is an independent module which loads the plate type starter bar onto itself. When disconnected, a rotating frame places the starter bar charging car into a horizontal position on the casting floor for starter bar head service, and to permit travel to the mold for starter bar feeding. The handling and charging device permits top and/or bottom feeding.
The entire modular caster can be completely assembled and aligned in any shop of a size with sufficient crane capacity. No machine component is left for field labor assembly.
The ladle turret module has an integral base which extends to the single foundation level. The turret is completely shop assembled with the turret bearing, drive assembly, lubrication piping and wiring in place. An additional, non-critical, bolted split is provided to separate the rotatable top from the base for shipment. Field labor need only install the base with built in bearing and rotating drive onto the embedded steel base plate and then place and bolt the rotatable top to the base.
The single level casting platform is designed to be prefabricated in modular forms to shift the emphasis from field construction to installation of modular assemblies.
The tundish car is designed to lift and lower the tundish for tundish nozzle insertion, to transfer the tundish in and out of the casting position and permit nozzle alignment with the molds. The large capacity tundish is equipped with throttling slide gates and has dams and weirs to promote float out of impurities. The tundish car also carries a part of the ladleman's platform which extends the modular floor mounted platform that carries the ladle shroud handler.
The mold design permits replacement of the mold jacket cartridge independent of the mold frame. Mold width can be automatically adjusted while casting.
The foundation mounted mold oscillator module has four eccentrics to generate the stroke, but is designed to eliminate all spherical bearings, bushing, pins, links and cam followers normally used for guidance. The mold oscillator permits very high oscillation frequencies, combined with extreme accuracy with virtually no wearing parts.
The oscillator base supports an adjustable segment in a manner permitting initial alignment of the segment by horizontal shifting without rotation, and rotation without horizontal shifting. Final machine alignment work in the field is reduced to checking and minor adjustments of pre-aligned components.
Labor forces are no longer required to field assemble machinery that should have been assembled in the manufacturer's work shop. The modular caster permits work shop assembly, alignment, and customer inspection of the whole caster at the manufacturer's plant before shipment.
Utility systems such as the electrical system, hydraulic system, water systems and instrumentation, are completely assembled in the form of system modules which we refer to as utility modules. The electrical system motor control room will be completely assembled at the manufacturer in a shippable module that can be placed near the caster. Hydraulic system pumps, tanks, filters, etc.; all equipment normally found in a hydraulic room, will be assembled by the hydraulic system supplier, inside a shippable module, which is then placed near the caster. Water systems and instrumentation systems will get the same treatment, so that all assembly and checkout is performed by the experts at point of manufacture, instead of by the field labor forces. The checked and tested control pulpit module is installed on the casting platform.
The utility modules and machinery modules are connected together by interconnecting modules which connect the various points on the machinery modules requiring coolant, electricity and hydraulic fluid to the sources in the utility modules.
The installation of the machinery modules, the interconnecting modules and the utility modules, which arrive at the job site in a virtually ready to operate condition, eliminate on site construction projects in favor of building block type installations.
The installation of interconnecting piping and wiring in the field typically takes a very long time and is extremely costly. Modular planning eliminates about 90% of all field installation of interconnecting wiring and piping. These modules which I have elected to call the interconnecting modules, are shippable, fabricated steel frames which are installed on the foundation mat near the machine components. They carry all the utility service lines and components in modular form. Interconnecting modules extend the utility lines along the casting machine by connecting to each other in series, and provide easily serviceable connections between the utility lines and the ultimate users on the machine. The only field work outside of the modular scope of coverage consists of the installation of the utility service line connecting the various utility modules to the interconnecting units. Transmission of electrical power, spray water, cooling water, compressed air, hydraulic fluid and lubrication grease is now accomplished through connectable, free-standing units, which are shipped to the job site as pre-tested modules.
Additional modules for the torch cut-off equipment and the runout tables complete the machine installation.
Some of the advantages of the ultra low head caster are lost if a vertical, straight mold caster or large radius caster is desired, but the general application and major benefits of the modular concept still apply.